forkprove is a forking version of prove that allows you to preload modules with -M and then run each test after forking, potentially makes most of the tests to run faster without an overhead of loading the same modules again and again, while having an isolated, clean testing environment with a fork.

Test::Aggregate allows you to create a nested TAP output by running a whole bunch of .t files from a directory.

forkprove shares the basic idea, but it creates a whole new test environment by making a copy of the process with fork for each test, which means it could run your tests that rely on the singleton state etc. without modifying the code to run with Test::Aggregate.

Your mileage might vary, if forkprove runs your tests faster or not. For lightweight modules, we've found that using forkprove doesn't make any siginificant difference, due to the fact that fork overhead nullifies the benefit of preloading modules.

On the other hand, test suite with Moose, Catalyst and Dist::Zilla seems to run 80-100% faster with forkprove and -jN option.